Genome-wide data has been used to prioritise the country’s tiger conservation efforts for the first time. A DBT supported paper published in Nature Scientific Reports has chalked out ways to identify and conserve genetically connected populations, as well as to maintain connectivity within them so as to carry out effective conservation efforts in the limited protected area available today.
Conservation of tigers is an international concern with tigers having lost 93% of their historical range worldwide. India plays a vital role in the conservation of tigers since nearly 60% of all wild tigers are currently found here. However, as protected areas are small and each area houses only a few individuals, many of them may not be independently viable. It is thus important to identify and conserve genetically connected populations, as well as to maintain connectivity within them.
A detailed blueprint prepared by a multi-institutional team working for five year highlighted that tiger population in northwest India requires conservation attention to ensure persistence of these tigers.
The team genotyped 10,184 SNPs from 38 individuals across 17 protected areas and identified three genetically distinct clusters (corresponding to northwest, southern and central India). They investigated genetic clusters for tigers in India, how the genetic variation is distributed among these genetic clusters and whether there are any signatures of differential local adaptation among these clusters.
The northwest cluster was isolated with low variation and high relatedness. The geographically large central cluster included tigers from central, northeastern and northern India, and had the highest variation. Most genetic diversity (62%) was shared among clusters, while unique variation was highest in the central cluster (8.5%) and lowest in the northwestern one (2%). The northwest cluster is currently represented by a single population, that is, Ranthambore Tiger Reserve. The authors did not detect signatures of differential selection or local adaptation.
The study investigated the reasons behind the diversification of the tiger population and indicated ways to strategise tiger conservation. It was a 5 year study supported by DBT at the Centre for Wildlife Studies (CWS) and National Center for Biological Sciences (NCBS). It also indicated how a study requires support of multiple stakeholders for its success.
The research was possible through the collective work of various agencies and scientists.The Forest Departments of Karnataka, Kerala, Rajasthan, Madhya Pradesh, Uttarakhand, Arunachal Pradesh, Assam, Orissa, West Bengal, Andhra Pradesh, Tamil Nadu and Maharashtra helped in obtaining the samples. The Centre for Cellular and Molecular Platforms (C-CAMP) provided facility for the Illumina sequencing runs. The National Tiger Conservation Authority and the Ministry of Environment, Forests and Climate Change provided the permissions for the project and lend their support.
Uma Ramakrishnan, scientist at National Center for Biological Sciences, Tata Institute of Fundamental Research, Bangalore and a Senior Fellow, Wellcome Trust/DBT India Alliance & Meghana Natesh PhD student at SASTRA University conducting research at National Center for Biological Sciences conceptualized the project. They hope the work will help guide tiger conservation in the years to come.